getnetbyaddr(3POSIX)

NAME | SYNOPSIS | DESCRIPTION | FILES | DIAGNOSTICS | ATTRIBUTES | SEE ALSO | BUGS

NAME

getnetent, getnetbyaddr, getnetbyname, setnetent, endnetent- get network entry

SYNOPSIS

#include <netdb.h>

struct netent * getnetent(void);
struct netent * getnetbyname(char * name);
struct netent * getnetbyaddr(long net, int type);
void setnetent(int stayopen);
void endnetent(void);

DESCRIPTION

The getnetent , getnetbyname , and getnetbyaddr functions each return a pointer to an object containing the broken-out fields of a line in the network data base /etc/networks . The object has the following structure:

struct netent { char* n_name; /* official name of net */ char** n_aliases; /* alias list */ int n_addrtype; /* net number type */ unsigned long n_net; /* net number */ };

The members of this structure are:

n_name

The official name of the network.

n_aliases

A zero terminated list of alternate names for the network.

n_addrtype

The type of the network number returned; currently only AF_INET.

n_net

The network number. Network numbers are returned in machine byte order.

The getnetent function reads the next line of the file, opening the file if necessary.

The setnetent function opens and rewinds the file. If the stayopen flag is non-zero, the net data base will not be closed after each call to getnetbyname or getnetbyaddr .

The endnetent function closes the file.

The getnetbyname and getnetbyaddr functions sequentially search from the beginning of the file until a matching net name or net address and type is found, or until EOF is encountered. Network numbers are supplied in host order.

FILES

/etc/networks

DIAGNOSTICS

A null pointer (0) is returned when EOF or an error is encountered.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Evolving

SEE ALSO

networks(4CC)

BUGS

The data space used by these functions is static; if the data will be required in the future, it should be copied before any subsequent calls to these functions overwrite it. Only Internet network numbers are currently understood.

NAME | SYNOPSIS | DESCRIPTION | FILES | DIAGNOSTICS | ATTRIBUTES | SEE ALSO | BUGS